Navigational instrument



Filed March 22, 1933 rn111iIIIIIIIIIIHIIIHIllvllulllyb lllll llltilulllnllnlll PATENT 1;"

3 Claims.,

(Granted under the act oi' Marel) 3,

amended April Sil,

Time invention seletes to e plotting instrument tor use in nevigstionend more particularly in netieeton.

lt is the objeetof this invention to provide o, device of the timementioned that is light, of convenient size end applicable to thesolution of large number oi nevigetionel problems.

With the above end other objects in View, the invention consists intl'ie construction, combinetlon end arrangement of parts as will behereinafter more fully described.

The drawing snows the form oi the invention 'that is et presentpieferred.

subject device is preferably mede oi" transoefent Celluloid or the likesind comprises e. elstie l lieviti@ one longitudinal edge calibratedwith e seele 2 .in inches end its opposite longitiif al edge e seele 3representing miles, els. the ooit es shown is 2o miles to the Pl seriesof parallel longitudinal lines i of parallel 'ttensverse lines 5 formlos eetellel lines.

miei preti etor t is set into one corner with. e itemize? l extendingtranssels? thereof sind lievine en edge 8 disposed dier/sete? or? tlf-.enretieotor sind also @lignes e edge of siede lo lee? :l 'plotieetoi e,tl'ie lest men hei/ing edges l?. end l2, rerc ien'ieter o the potractoi*la tlie edjecent longitudinsl 13 is formed between 'meten tllougliwhich to serve e. pivot about lie rotated. Edges in the seme units seele"lie girotrectoi'. Likerl in units of seele protrectoz es .zere

L, tions lom the zero point on e. llt that edge of ble-,de l thateelt-ties s angles in either direction from the nero peint may be reeddirectly. lThe sets el lines 5 efe provided to adept the instrument lo?parallel lines on o, chart. elles to the inch, tlie erssnl plottingsheet end. the :aircraft Meloetor the center of the proired point onsheet,

N28; 370 t). G., 757) the instrument can be rotated about tliet centerand bearings and distances will be shown directly, or with the zero ofthe scale on the northn south line the protractor can be used. to merlibearings. 5

It will be understood that the above description and accompanyingdrawing comprehend only the general and preferred embodiment of myinvention and that various changes in construen tion, proportion andarrangement of parts may be made Within the scope of the appended claimswithout sacrificing any of the edventegesoi.' my invention.

The invention described herein may loe manufiactured and used by or forthe Government of the United States of Amc-rice. for governmentalpurposes without the peymentol any royalties thermo or therefor.

l claim:

i. in e navigational instmn'ient, e blade leaving' its longitudinal,edges celi'ereted in units of tence, the calibrations on one edgelieingof diierm ent magnitude from those on the other, seid blade leaving onit two sets of pesallei lines form ing a. rectangular grid, en annulerprotrsctor set into one cornes et islande, e member eeross seidniettemleaving e metrel seid gesteente?? eine n W ll. en end of seidblade, e second member extending from seid :erst member the protesterend. listing an edge aligned t lateral edge ot seid lolede. end thirdniemeer extending. iiom opposite side et tile first member' to theprot-,rector end nei/*mg edge eliesneci with seid letters esige, tneseid eligned edgesfo the second e, third members img on opposite sides0;" ebemetei in with seid leteiel edge o the blade, the dlenietreledges. ot seid tliiee members being.' celiliietet in tlie seme unitsthat edge el" t "siede with which. the second end third meinte ere endthere beine' e smell epestuze de ned et the eenter of seid protreetot.

lo. nsvisetionel instamment, e, siede leef/H ing its longitudinal edgescalibrated in uni s of distsnee, tlie eslioietions one edge diderentmagnitude from those on the other, seit blade having on it two sets ofparallel lines fom; ine' e. rectengular geld, en :simuler protrector setinto one corner of seid lnlede' end. inteeielly united with. seid blade,s. member extending este seid proteetor liet-ing one edge on. di wettline oi' 'protreetor end aligned w n edge ozl seid iolede to constitutece said erige end other members Corine site sides oi? the first member i.i thereof, e protractoi se?J into 2, seid blade adjacent said edge withits said edge and integrally united with said biade, e member exi-endingaeicrss sei pretzector having all edge aligned with an @mi of saisiblade emo". on a diameter of the e ai @0i-nei' of; center aligned Wihpfmarecor im.: dma e, (nominee-tion (if euch seid edge being caiibreicedim me unibs FREIE? VAN EIGEN

